CDMA AND NARROWBAND MULTIUSER DETECTION WITH ANTENNA ARRAYS*

JAMES K. CAVERS

CLASS NOTES

MOTIVATION (pdf)

Preread: K.S. Gilhousen et al., “On the Capacity of a Cellular CDMA System,” IEEE Trans. Veh. Technol., vol. 40, no. 2, pp. 303-312, May 1991

1.1 Multiuser Detection and the Claims

1.2 MUD and the Capacity of Simple CDMA

1.3 Structure and Objectives of the Course

THE CDMA SIGNAL ENVIRONMENT

Preread: Your first digital communications text (e.g. Proakis or Haykin or Wozencraft & Jacobs) on vector representation of signals, projection onto signal space, filters and correlators matched to signals and to an orthonormal basis, MAP and ML decisions. If you don’t have them handy, look over Appendix E. Also scan [Rooy00].

2.1 The Transmitted Signals (pdf)

2.2 The Received Signals (pdf)

2.3 Sufficient Statistics in CDMA (pdf)

2.4 The MUD Problem (pdf)

2.5 Plausibility of MUD Claims (pdf)

PROPAGATION, FADING AND DIVERSITY

3.1 Scattering Channels (pdf)

3.2 Effect of Fading on Single-User BER (pdf)

3.3 Diversity Reception – Single User (pdf)

3.4 Diversity Reception – Multiple Users (pdf) (readings)

3.5 Gaussian Quadratic Forms in Detection Problems (pdf)

3.6 Imperfect Channel Estimates in Fading and Diversity (pdf)

3.7 Rank and Dimensionality in Diversity Reception (pdf)

CDMA MULTIUSER DETECTION WITH LINEAR RECEIVERS

4.1 Linear Receivers (pdf)

4.2 Rank and Dimensionality (pdf)

4.3 Implementation of Linear Receivers (pdf)

4.4 Error Performance of Linear Receivers (pdf)

DECISION FEEDBACK AND WHITENING RECEIVERS

5.1 Unmodified Decision Feedback (pdf)

5.2 The MMSE DFE (pdf)

5.3 DF With Noise Whitening (pdf)

5.4 Implementing Whitening Decision Feedback (pdf)

MAXIMUM LIKELIHOOD MULTIUSER DETECTION

6.1 ML-MUD Without Signatures (pdf) (readings)

6.B Simulation of MUD Without Signatures (pdf)

6.C Approximations of ML for Narrowband Signals (pdf) (readings)

6.D Simulation Comparison of SIC Methods (pdf)

6.E Perspectives on Narrowband MUD (pdf)

6.2 ML-MUD With Signatures: Classic Results (pdf)

6.3 ML-MUD for CDMA: Problem Setup (pdf)

6.4 Tree Searching in ML CDMA (pdf)

6.5 A Role for ML-MUD in CDMA Systems (pdf)

INTERFERENCE CANCELLATION

7.1 Background (pdf)

7.2 Linear Interference Cancellation (pdf)

7.3 An Interference Cancellation Pipeline (pdf)

7.4 A Nonlinear Method – Successive IC (pdf)

7.5 Another Nonlinear Method – Parallel IC (pdf)

7.6 Decision Nonlinearities (pdf)

7.7 Partial Parallel Interference Cancellation (pdf)

7.8 Constrained ML Detection (pdf)

7.9 Some Questions (pdf)

APPENDICES

A: MUD AND CDMA CAPACITY (pdf)

B: COMPLEX ENVELOPE NOTATION (being adapted, still pretty scruffy)

B1. The Complex Envelope (pdf)

B2. Bandpass Random Processes (pdf)

B3. Bandpass Sampling (pdf)

B4. Complex Gaussian Vectors (pdf)

C: RECEIVED MULTIUSER WAVEFORMS (pdf)

D: RECEIVED MULTIUSER SIGNAL FOCUSED ON CHANNEL GAINS (pdf)

E: ELEMENTARY DETECTION THEORY (from course notes, ENSC 428)

E1. Signal Space (pdf)

E2. Orthogonal, Nonorthogonal and Complete Bases (pdf-a, pdf-b)

E3. Detection in White Noise (pdf)

F: SUFFICIENT STATISTICS (pdf) (from course notes, ENSC 810)

G: RAYLEIGH, RICE AND CHI-SQUARED STATISTICS

H. MAXIMAL RATIO COMBINING (pdf)

I. SIMPLIFICATION OF MULTIUSER DIVERSITY MODEL (pdf)

J. ZERO FORCING GIVES MAXIMAL RATIO OF LOWER DEGREE (pdf)

K. DERIVATIVES AND GRADIENTS WITH RESPECT TO COMPLEX VARIABLES (pdf)

L. EXAMPLES OF DETECTORS DESCRIBABLE BY GAUSSIAN QUADRATIC FORMS (pdf)

M. CHARACTERISTIC FUNCTION OF A GAUSSIAN QUADRATIC FORM (pdf)

N. THE TWO-SIDED LAPLACE TRANSFORM (pdf)

O. NUMERICAL SOLUTION OF LINEAR EQUATIONS (pdf)

P. GRAM-SCHMIDT ORTHOGONALIZATION (pdf)

Q. MATRIX INVERSION LEMMA AND WOODBURY’S IDENTITY (pdf)

R. MAXIMUM LIKELIHOOD DETECTION IS UNAFFECTED BY INVERTIBLE TRANSFORMATIONS (pdf)

INTERACTIVE DEMOS

REFERENCES (pdf)

Note references will be updated frequently during the course, so download new copies from time to time.